Rethinking SIDS: Many Deaths No Longer A Mystery : NPR
www.npr.org

For years, little was known about why babies died suddenly and unexpectedly in their sleep. But now, many of these deaths are believed to be preventable accidents caused by unsafe sleep practices. That's led some to question whether the term sudden infant death syndrome is still relevant.

I disagree
One size doesn't it all.

I think Moon, is pushing her own belief.  Sleeping on the back is OK if your not congested in the lungs with mucous. for starters.
If I had a child who was chocked up with mucous, a Cystic Fibrosis baby for instance I would be postural draining, as in sleeping the child side to side, or they might choke and die on their backs.

Most SIDS deaths are unexplained not suffocation from the bedding or toys.  Those deaths are usually determined as suffocation accidents and not falsely labeled SIDS.  In the past in fact, it was more common to have written suffocation on the death certificate than SIDS and falsely blame the pet cat or such like to try to explain the death. 
To say that "All the babies who died suddenly and unexpectedly have all died in unsafe sleep environments," Moon says. "These are all cases that could have been prevented."I find very cruel to the great many parents of SIDS death babies who were highly educated about providing safe environments for their children.

I think her statement may be true in her locality but it is far from the facts overall. I have known of too many intelligent parents who have had a SIDS death in the family or a close call with one, to believe this.  Also have a medical background and have never seen any evidence that most cases called SIDS were accidental suffocation.